Leaders of UC Berkeley’s Greek system have taken the unusual step of suspending social activities in the wake of reports that two students were sexually assaulted at fraternity parties last weekend.

Calling the incidents “vile and unjust,” the campuswide fraternity council announced the decision Tuesday on its Facebook page.

“The (Interfraternity Council) has voluntarily decided to suspend all social events until we can re-evaluate our risk management practices and care for those who have been affected,” the statement said.

One woman told Berkeley police she was sexually assaulted by an acquaintance on the morning of Oct. 15. Another reported “unwanted sexual conduct” on Oct. 14, according to an alert from UC Berkeley’s campus police department.

The Berkeley Police Department is investigating both cases. Campus police issued two crime alerts in close succession on Monday evening.

While sexual assault is known to be vastly underreported, a wave of activism at UC Berkeley and other college campuses in recent years may have encouraged more victims to come forward. Annual crime statistics updated this month show UC Berkeley received 45 reports of rape and other sex offenses in 2015, compared to 23 in 2012.

The statement from the Interfraternity Council suggests that the perpetrators may not belong to campus fraternities.

“While we have no reason to believe that these were committed by fraternity men on this campus, it is still disheartening and alarming that they have occurred on fraternity property,” it said. “We wish to reiterate our pledge to eliminate sexual violence from our community and reaffirm our commitment to our members and students of Berkeley to provide a safe environment for all.

“At the same time, we recognize the immense courage it took for the survivors to report these crimes and will do everything in our power to respect their privacy and their wishes.”

Katy Murphy is based in Sacramento and covers state government for The Mercury News and East Bay Times, a beat she took on in January 2017. Before that, she was the news organization's higher education reporter, writing about UC, CSU, community colleges and private colleges. Long ago, she covered Oakland schools and other K-12 education issues.

Violent police encounters in California last year led to the deaths of 157 people and six officers, the state attorney general’s office said Thursday in a report that provides the first statewide tally on police use-of-force incidents.